A configuration of a vehicle that includes: a gear mechanism and a belt-type continuously variable transmission that are provided in parallel; and plural clutch mechanisms for switching a torque transmission path, which stretches from a power source to drive wheels, to a transmission path including a continuously variable transmission or to a transmission path including a transmission mechanism has been described in Japanese Utility Model Application Publication No. 62-45455 (JP 62-45455 U). The configuration described in JP 62-45455 U is configured to be able to switch the torque transmission path, which stretches from the power source to the drive wheels, to the path including the belt-type continuously variable transmission or to the path including the gear mechanism and set a neutral state by combinations of the clutch mechanisms in engaged states or in disengaged states.
By the way, it has been known to directly connect a torque transmission path between an internal combustion engine and drive wheels in a vehicle including the internal combustion engine as a power source, in order to improve fuel economy by reducing power loss. In this case, vibrations and noise, such as front-rear and up-down vibrations of the vehicle and booming noise in a vehicle cabin, are possibly generated due to a vibration that is generated by explosion of fuel in the internal combustion engine, that is, transmission of a vibration that is generated when the internal combustion engine outputs torque to the torque transmission path. For this reason, as configurations for damping the vibration that is transmitted to the torque transmission path, a configuration for transmitting the torque via a fluid, a configuration for making the vehicle run by setting a relatively high gear ratio (transmission gear ratio) in a directly-connected state and controlling a speed of the internal combustion engine in a high speed state, a configuration for arranging a damper (a vibration damping device) with relatively low rigidity in the torque transmission path, a configuration for providing inertial moment in the torque transmission path by an inertial mass body, such as by increasing a mass of a flywheel that is coupled to the internal combustion engine, and the like have been known.
However, in the configuration described in above-described JP 62-45455 U, while it is possible to suppress transmission of the vibration, which is generated when the internal combustion engine outputs the torque, to the torque transmission path by a fluid transmission device, transmission efficiency for transmitting the torque via the fluid is degraded. Supposedly, in the case where the speed of the internal combustion engine is increased so as to dampen the vibration transmitted to the torque transmission path, the internal combustion engine cannot be driven in an operation range where the fuel can be saved. Accordingly, while the vibration can be dampened, the fuel economy is possibly degraded. In addition, in the case where the mass of the flywheel is increased, the vibration transmitted to the torque transmission path can be dampened by the inertial moment of the flywheel. However, in conjunction with an increase in the mass of the flywheel, an inertial force in the torque transmission path is increased, and the fuel economy is thereby degraded. Furthermore, a powertrain is increased in size due to an increase in weight of the unit.